PHP Warning: Undefined property: ole_pps_file::$_PPS_FILE

[myoustal]

PHP file
require_once plugin_dir_path( dirname( FILE ) ) . 'class.writeexcel_biffwriter.inc.php';
require_once plugin_dir_path( dirname( FILE ) ) . 'class.writeexcel_format.inc.php';
require_once plugin_dir_path( dirname( FILE ) ) . 'class.writeexcel_formula_jmb.inc.php';
require_once plugin_dir_path( dirname( FILE ) ) . 'class.writeexcel_olewriter.inc.php';
require_once plugin_dir_path( dirname( FILE ) ) . 'class.writeexcel_workbook.inc.php';
require_once plugin_dir_path( dirname( FILE ) ) . 'class.writeexcel_workbookbig.inc.php';
require_once plugin_dir_path( dirname( FILE ) ) . 'class.writeexcel_worksheet.inc.php';
require_once plugin_dir_path( dirname( FILE ) ) . 'functions.writeexcel_utility.inc.php';

Executing
$fname = tempnam(sys_get_temp_dir(), "bigfile.xls");
$workbook = new writeexcel_workbookbig($fname);
$worksheet = $workbook->addworksheet();
$workbook->close();
unlink($fname);

Get error
PHP Warning: Undefined property: ole_pps_file::$_PPS_FILE in [path here]/class.ole_pps_file.php on line 65
PHP Warning: Undefined property: ole_pps_file::$_PPS_FILE in [path here]/class.ole_pps_file.php on line 65
PHP Warning: Undefined property: ole_pps_file::$_PPS_FILE in [path here]/class.ole_pps_file.php on line 65
PHP Warning: Undefined property: stdClass::$_BIG_BLOCK_SIZE in [path here]/class.ole_pps_root.php on line 56
PHP Warning: Undefined property: stdClass::$_SMALL_BLOCK_SIZE in [path here]/class.ole_pps_root.php on line 58
PHP Warning: Undefined variable $sRes in [path here]/class.ole_pps.php on line 172
PHP Warning: Undefined property: ole_pps_root::$_PPS_FILE in [path here]/class.ole_pps.php on line 110